Method of and apparatus for modifying color of vacuum tube lights



Oct. 13, 1931. BECK 1,827,704

METHOD OF AND APPARATUS FOR MODIFYING COLOR OF VACUUM TUBE LIGHTS Filed Sept. 8. 1927 g-nvamtoz LEO L. EEC/1'.

$3) GHQ 01401 4 column of more or less rarefied gas,

Patented ea. 13, 1931 1,327,704

UNETED STATES PATENT OFFICE:

LEO L..BECK, OF JACKSON HEIGHTS, NEW YORK, ASSIGNOR TO CLAUDE NEON LIGHTS, ENG, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK METHOD OF AND APPARATUS FOR MODIFYING COLOR 0F VACUUM TUBE LIGHTS Application filed September 8, 1927. Serial No. 218,182.

This invention relates to lighting systems, parative intensity of the rays may be affected, such, for example, as that comprisingthe well however. The color of the light depends known neon lights, in which the passage of a upon the comparative intensity of the rays high potential alternating current through a and it is by affecting this condition-that the such as modification of the light in accordance with neon, causes the tube contents to glow and this invention is obtained. radiate light. For example a tube filled with pure neon Heretofore, the color of light emitted by emits a red orange light at a low frequency, the contents of a luminescent tube has not say 60 cycles, whereas at a higher frequency been modified permanently or even for a preit will emit a yellow orange light. At low determined prolonged period. A momenfrequency the green rays are the more intary modification of the light emitted from a tense. This is a common characteristic of gaseous mixture enclosed in a luminescent such gases. For instance, helium, excited at tube has been produced by abruptly varying low frequency, emits a pinkish yellow light the current passing through the tube, but this whereas at high frequency the light is more 65 has obviously not resulted in a permanent of a violet color. This is because at a low maintenance of the modified color. lVith a frequency the red and yellow rays predomimixture of gases and metallic vapors, such nate whereas, atahigher frequency,the violet as neon and mercury vapor, one alone of the rays predominate. With a mixture of a gas, components has been caused to vibrate under. say neon, and a vapor, say mercury vapor, the action of the electric discharge between in a luminescent tube, the mercury vapor vithe terminals and has emitted its characterbrates alone at low frequency and the tube istic color, that is, the same color as if it mit a bl e light, If the excitation is efwere alone contained within a tube. Either fected at high frequency the neon vibrates the neon gas alone commenced to vibrate or at the same time as the mercury and there the mercury vapor alone commenced to vimay be observed in the spectrum the simulbrate depending upon conditions, but it has taneous presence of the spectrum of neon and heretofore been found impossible, in a given the spectrum of mercury and this is stable. portion of the tube, to obtain a mixture of The light thus emitted by the tube is neither light from both the neon gas and the mercury the blue of the mercury nor the reddish color vapor which was of a color applicable to lighting.

- The present invention seeks a'stable manof the neon gas but is a mixture of the two and is of a pinkish color. With a mixture of helium and mercury vapor. at low frequency,

ner of obtaining a modification of the color the tube emits a greenish light while at high I of the light emitted by a luminescent tube. frequency the tube emits a yellowish light.

To this end the color of the light emitted by The object of the present invention S all such a tube is varied or modified and the apparatus by which the foregoing results modified color maintained constant or stable may be realized. In carrying out the invenby changing he frequency o e alte nating tion a vacuum tube is included in an oscillatcurrent passing through the tube. V ing circuit. The voltage is, of course, main- 99 V The color o t i from a pu gas e tained atahigh value, as that isawell known closed in a luminescent tube, electrically eX- requirement for the operation of rarefied gas cited, depends upon the number of the rays tubes. The necessary high voltage is conin the Spectrum, on the Position f the rays in veniently obtained from the usual industrial the spectrum andon the comparative intensisupply by means of a transformer. T0 efi'ect ty of the rays. The number of the rays and the variation in the color of the light usually their position in the spectrum do not change, emitted from the vacuum tube and to mainwhatever may be the process utilized to protain that color constant under unchanging duce the spectrum and this constitutes a conconditions the frequency of the current fed nt Characteristic 0f the g he omto the tube is increased materially over the 109 normal frequency by suitable frequency description of a preferredembodiment thereof, taken in connection with the accompanying drawing which illustrates, conventionally, a rarefied gas tube, adapted for selective connection with either low frequency circuit or a non-oscillating circuit.

In the lighting system as illustrated the tubular envelope 6 of the tube light containing a rarefied gas, such as neon, or helium or like alone, or mixtures of such gases or a mixture of a gas with a metallic vapor, such as mercury vapor, is shown as having bulb portions 7 carrying electrodes 8 mountedon lead-in wires 9 and 10 respectively, each passing through a press 11. The tube 6 is connected by the leads 9 and 10 with either an oscillating circuit of high frequency or an oscillating circuit of low frequency.

Referring first to the low frequency oscillating circuit a source of low potential alternating current is indicated at G connected with mainconductors 15 and 16 which may represent the usual industrial alternating current supply at, say a frequency of cycles. These mains 15 and 16 are connected, respectively to the terminals 11 and 12 of a circuit se lecting device, such as a double pole switch 13, by which an electrical connection may be selectively made with either the high frequency oscillating circuit or the low frequency oscillating circuit. Obviously this selection of circuits may be made manually by means of the switch 13 as shown, or mechanically, to throw in the respective circuits periodically in predetermined manner.

To operate the tube 6 for the purpose of. obtaining the-usual light emitted by the tube contents at normal frequency, the mains 15 and 16 are respectively connectedby thecir- 4 cuit selector 13 with the contacts 2 and4whi ch are connected by the leads 18 and 19 with the terminals of the primary coil 20 of the transformer 21. The secondary coil 22 of the transformer 21 is connected with the leads 9 and 10 by the wires 23 and 24 so that the quency, in a manner well understood, to give tube 6 may be electrically connected with the transformer 21 and operated from the commercial supply mains 15 and 16 at the requisite high potential, but at normal fre- The transformer 21 may take any form suitable to the situation, that is, it may be a leak transformer in order that it may compensate for the negative resistance of the tube or if an ordinary commercial transformer is used, a reactance or other current controlling device (not shown) may be included in the circuit for the same purpose, as will be understood.

For the operation of the tube 6 at high frequency, in the attainment of a modification of a color emitted by the tube contents the tube is included in a high frequency oscillating circuit. The switch 13 is availed of to disconnect the source of current of normal frequency from the low frequency oscillating circuit and connect the said source with the high frequency oscillating circuit, including the switch contacts 1 and 3, such as will now be described.

Connected with the leads 9 and 10 of the tube 6 as by the wires 25 and 26 and in parallel with the secondary coil 22 just described is the primary coil 27 of the transformer 28 whereof the secondary coil 29 is included in the oscillating circuit through the wires 31, 32 leading to the contacts 1 and '3 of switch 13.

The constants of the oscillating circuit are so designed as to permit the tube 6 to be operated through the instrumentality of the transformer 28, at a much higher frequency, say 5000 cycles, than when operated from the transformer 21 byincluding frequencychanging means in the oscillating circuit with transformer 28.

Terminal 1 may be connected at one terminal of the primary coil 29 by the lead 31 while a condenser 33 is interposed in series with switch terminal 3 and the other terminal of the primary coil 29 and across the condenser there is shown connected a current breaker 34.

It will thus be seen that by the circuits described and by properly proportioning the constants of the circuit, the comparative intensity of the rays of the spectrum of the tube contents may be modified and thus the color of the light therein produced, modified. Furthermore, by the disposition of the component elements disclosed, the operation of the tube, commercially, with apparatus as now developed may be realized and the substitution of any well known form of primary flasher for the switch 13 is permitted without incurring the liability to destructive arcing were a circuit delivery high frequency alternating current to be selectively interconnected with the leads 9 and 10 of the tube 6. In addition the disconnection of the low frequency circuit obviates any power loss in the primary coil of transformer 20 as would be the case were that coil continuously fed by the mains 15 and 16, while the secondary coil 22 although in parallel with the tube 6 will not shunt the tube due to the fact that its with the alternating current at low frequency in the usual .way as indicated by the circuit including the transformer 21 to cause the tube to radiate light of its characteristic color or it may be supplied as desired with a high to the source of'alternating current, a sec} 'ond transformer whereof the secondary coil frequency current, asby the circuit including the transformer 28 and the tube will instantly light up with an altered color which may be maintained as long as desired. Furthermore, the intervals of time between operating the tube at low frequency and high frequency may also be prolonged as desired, which differentiates the process from those prior known experiments in which a temporary instantaneous change in color is obtained by varying the current.

Various substitutions may be made among the component elements of the circuits by which the invention is shown as being realized. Furthermore the invention is not to be deemed limited to a combination including both an oscillatory circuit and a nonoscillatory circuit but the inclusion of the non-oscillatory circuit is to be deemed per-.

missive and has been illustrated in order to show the widest usefulness of the invention.

hat I claim is: 1. A lighting system comprising the com- .bination with a luminescent tube and a source of alternating current at low frequency and. low voltage, of a transformer whereof the secondary coil is connected with the tube terminals, 2. high frequency oscillatory circuit including the primary coil of the transformer and a circuit closingdevice selective ly connecting the source of current at low frequency and voltage with the high frequency oscillatory circuit.

2. A lighting systemcomprising the combination with a luminescent tube and a source of alternating current at low voltage and fre= quency, of a transformer whereofthe sec ondary coil is in circuit with the tube, a low frequency circuit including the primary coil of the transformer adapted to be connected is in circuit with the tube in parallel with the secondary coil of the first named transformer,

a high frequency oscillatory circuit including the primary coil of the second transformer: and means to selectively connect the. high frequency and low frequency circuits with the source of low voltage alternating current.

3. A lighting system comprising the combination with a luminescent tube and a source of alternating current at low frequency and low voltage, of a transformer whereof the secondary coil is in circuit with the tube, a low frequency circuit including the primary coil of the transformer, a second transformer whereof thesecondary coil is in circuit with the tube in parallel withthe secondary coil of the first named transformer, a high frequency circuit including the primary coil of the second transformer, means to selectively connect the high frequency oscillatory and low frequency circuits with the low voltage source of alternating current, and means to prfivent either secondary coil shunting the tu e.

4. A lighting system comprising the combinationwith a luminescent tube and a source of alternating current at low frequency and low voltage, of a transformer whereof the secondary coil is in circuit with the tube, a circuit including the primary coil of the transformer, a second transformer whereof the secondary coil is in circuit with the tube in parallel with the secondary coil of the first named transformer, a high frequency oscillatory circuit including the primary coil of the second transformer and means to selectively connect one of the two circuits with the source of low voltage alternating current, the secondary coil of the second named transformer having an impedance relatively higher than the resistance of'the tube.

5. A lighting system comprising the combination with a luminescent tube and a source of alternating current at low frequency and low voltage, of a transformer whereof the secondary coil is in circuit with the tube, a low frequency circuit including the. primary coil of the transformer, a second transformer whereof the secondary coil is in circuit with the tube in parallel with the secondary coil of ance relatively higher than the resistance of the tube. s

6. A lighting system comprising the combination with a luminescent tube and a source of alternating current at low frequency and low voltage, of a transformer whereof the secondary coil is in circuit with the tube, a- "low frequency oscillatory circuit including the primary coil of the transformer, a second transformer whereof the secondary coil is in circuit with the tube-in parallel with the secondary coil of the first named transformer, a high'frequency oscillatory circuit including the primary coil of the second transformer and 'means to selectively connect the high frequency oscillatory and low frequency oscillatory circuits with the. source of low voltage alternating current, the impedance of the secondary coils of both transformers being .relatively greater than the resistance of the tube.

7. A lighting system comprising in combination a luminescent tube charged with a mixture of two gases or vapors or a gas and vapor, a source of alternating current at low frequency and low voltage, means connected to the tube to transform the low voltage to a high voltage, means connected to the tube to transform the low voltage and frequency to a high voltage and high frequency, and means Cto selectively connect the source of low voltage alternating current to one of the said means.

8. A lighting system comprising the combination with a luminescent tube containing mercury and a rare gas and a source of alternating current at low frequency and low voltage, of a transformer whereof the secondary coil is connected to the tube terminals, a high frequency circuit including the primary coil of the transformer, and a circuit closing means adapted to select vely connect the source of alternating low voltage current with I the high frequency circuit.

40 a a circuit closer interposed between said low 9. A lighting system comprising a luminescent tube, a low frequency circuit and a high frequency circuit connected to said tube, a source of low voltage and low frequency current, and a circuit closer interposed between said low voltage source of current and said low and high. frequency circuits and adap' ed to connect either of said circuits with said source of low voltage current.

10. A lighting system comprising a lumi- ,nescent tube containing a rare gas and mercury, a low frequency circuit and a high frequency circuit connected to said tube, a source of low voltage and low frequency current, and

voltage source of current and said low and high frequency circuitsand adapted to connecteither of said circuits. with said source of'low voltage current.

In testimony whereof I afix my signature.

LEO L. BECK;

CERFKFZGATE 0F CORRECTION.

Patent No. 1,827,704. Granted October 13, 1931, to

LEO L. BECK.

it is hereby certified that error appears in the printed specification of the aheve numbered patent requiring correction as follows: Page 2, iine 18, for the Werd "tow" read a high, and tine 19, for the compound word "non-oscillating" read flow thequency; line 101 to: J'at"- read to, and line 121, for "delivery" read delivering; and that the said Letters Patent should be read with these correetions therein that the same mayeonform to the recordof the case in the Eatent @Efiee.

Signed and seated this Sthday of December, A. D. 1931.

M, 5. Meme, (Seat) Acting Commissioner of Patents. 

